Friction controlled slidable and rotatable mounting for lamps



MOUNTING FOR LAMPS Filed March 6 1965 J. WARSHAWSKY FRICTION CONTROLLEDSLIDABLE AND ROTATABLE 6 l I i: T. 9 I 5 w Patented May 25, 12 34653,185,S38 FRICTIJN CUNTRGLLED SLlDAllLE AND RQTAT. ABLE MGUNTBNC 58RLAMPS Jerome Warshawslry, 3285 Bertha Drive, Baldwin, N.Y. Filed Mar. 6,1963, Ser. No. 263,317 3 Claims. (Cl. 2445-31) This invention relates totable and floor lamps and more particularly is directed to an improvedmeans for adjustably mounting a light source for axial and rotatablemovement with respect to a vertically disposed cylindrical support.

Among the objects of the invention is to provide an improved clutchmeans for sliding along and rotating with respect to a cylindricalsupport member, which shall comprise few and simple parts arranged andconstructed in a novel manner to require a minimum of time and labor forassembly in quantity low cost production, which clutch shall beself-lubricating and non-abrasive to insure against scratching orotherwise marring the polished finish of the cylindrical supportparticularly when made of brass, which will not bind or freeze the partstogether and yet will permit easy adjustment of the tightness betweenthe movable parts to meet weight requirements of the light source andassociated structure and also satisfy individual needs which shall berugged to withstand rough usage and efiicient and practical to a highdegree in use.

Other objects of the invention will in part be obvious and in parthereinafter pointed out.

The invention accordingly consists of features of constructioncombination of elements and arrangement of parts which will beexemplified in the construction hereinafter disclosed the scope of theapplication of which will be indicated in the claims following:

In the accompanying drawing in which an illustrative embodiment of theinvention is shown:

FIG. 1 is a side elevational view of a table lamp constructed to embodythe invention having a vertically upstanding cylindrical support alongwhich a clutch member carrying a light source is slidably and rotatablymounted.

FIG. 2 is an enlarged exploded perspective view of the clutch membershown in FIG. I removed from assembly on the cylindrical support showingdetails of construction.

FIG. 3 is a fragmentary vertical sectional view taken along line 33 inFIG. 1 showing the clutch parts in position for relatively looseoperation, and

FIG. 4 is a fragmentary vertical section similar to FIG. 3 but showingthe parts in position for tight operation.

Referring in detail to the drawing, it generally denotes a lamp orlighting unit which may be of a floor standing type or as here shown adesk or table type where in a light source is mounted for verticaladjustment along and rotatable about a substantially vertically disposedcylindrical support 12 upstanding from a base ll. The light source maybe of any desired structure and design ere shown to comprise an electricbulb 13 mounted in a socket 14 which may carry a shade l5 and beconnected to terminate an arm 16 by a swivel fitting 1'7. The oppositeend of arm 16 is carried by a clutch member 18 and attached thereto inany well understood manner to receive electric wiring W therethrough forenergizing bulb 13. Clutch member 18 may be constructed to carry morethan one arm 16 or equivalent element arranged symmetrically orotherwise about support 12.

Clutch member 18 is formed with a bore 18a having one end thereaded asat 1812 and an opposite end 18a of reduced diameter. A bushing 19 snuglyfits bore 18a and in turn is formed with an axial bore 19:: snuglyreceiving support 12 for rotation thereon and axial movement therealong.Compression nut 2t! having an axial bore 29a is formed with anexternally threaded end Ztlb for engaging clutch member threads 18b andmay be manipulated by knurled head 2490 to abut and exert pressure uponbushing 19.

As is clear from FIG. 3 the diameter of bore 20a is substantially equalto the reduced diameter of bore end 18c the latter and bore Zita beingsuificiently larger than the outside diameter of support 12 to preventcontact therewith in operation of clutch member 18.

A feature of the invention is the elimination of drawbacks inherent inexisting devices by providing controlled sliding of clutch member 18vertically along support 12 whereby the latter is suificiently grippedto counteract the combined weight of clutch member 18 and the lightsource structure carried thereby which controlled sliding incorporatessimple and efiicient means for adjusting the degree or" said gripping inaccordance with requirements. Thus bushing 19 is formed of anelastomeric resinous plastic material having non-compressible semi-rigiddeformable non-adhesive moderately self-lubricating non-abrasiveproperties and is provided of sufiicient length that is, axiallyelongated, to prevent metal against metal contact, namely, contact ofbore end 18c and bore 259:: with support 12 due to moments of torqueexerted on clutch member 18 along an axis at right angles to that ofbore 38a.

To accomplish these ends, bushing l9 may be made of polyethylene tubinghaving a hardness of 35 to 5G durorn eter. When used on a support 12 of/2 inch diameter, bushing 19 cut to a length of about /5 inch and havinga wall thickness exceeding 1 inch renders satisfactory results. It is tobe understood that varying the diameter of support 12 maycorrespondingly vary the dimensional requirements of bushing 19.

In order to facilitate the controlled sliding of clutch member 18 onsupport 12 whereby satisfactory operation may be obtained utilizing lesscritical tolerances between the coacting parts with correspondingreduction of manufacturing costs, at least one of the surfaces engagingthe opposite ends of bushing 19 may be beveled inwardly.

To achieve a balanced gripping, FIGS. 3 and 4 show both such endengaging surfaces, namely, interior shoulder 18d of bore 18a and endedge 2th! of compression nut 25), beveled inwardly to provide surfacesfor simultaneously deforming the opposite ends of bushing 19 against thesurface of support 12.

After the parts are made as shown in the drawing and described above,clutch member 18 is first assembled by inserting bushing 19 into bore18:: through threaded end 13b and compression nut 2th is looselythreaded into the latter. The clutch member assembly is then mounted onsupport 12 by inserting a free end thereof through bushing bore 19a.Compression nut 29 may then be tightened to the position shown in FIG. 3wherein bushing 19 is only slightly distorted to apply a relativelysmall friction force between bushing 19 and support 12 for relativelyfree sliding movement of clutch member 18 along support 12.

In practice, support 12 in assembly with clutch member 18 may besupplied as a fitting to lamp manufacturers who complete lighting unitIn in any of a large variety of designs and styles.

The practical operation and utility of lighting unit lltl incorporatingthe controlled slidable and rotatable mounting of clutch member 18 onsupport 12 will now be apparent. Compression nut is tightened orloosened by finger manipulation of knurled head Ede to respectivelyincrease or decrease the pressure exerted by bushing 19 on support 12.As compression nut 26 is tightened from the position shown in FIG. 3 tothat of FIG. 4, the opposite ends of bushing 19 are deformed from theirnormally squared-off ends to conform to beveled surfaces 18d and 29dwhereby a maximum gripping pressure is exerted on support 12. Thuscompression nut 22% may be selectively tightened to provide thenecessary degree of gripping to support the Weight of clutch member 18and its associated structure against downward sliding by gravity and forease of desired operation. After the proper setting of compression nut29 is ascertained, the height and relative position of clutch member 18with respect to support 12 may be adjusted with relative ease.

The construction embodying the invention hereinbefore described isparticularly suitable for use in quality brass lamps wherein thesurfaces are customarily protected against discoloration by theapplication of a bakedlacquer coating. Support 12 when protected by suchcoating will not be marred by the sliding or rotating thereon of clutchmember 18 having bushing 19 of a self-lubricating non-abrasiveelastomeric plastic.

It is thus seen that there is provided an improved friction controlledslidable and rotatable mounting for lamps whereby the several objects ofthis invention are achieved and which is well adapted to meet theconditions of practical use.

As various possible embodiments might be made of the above invention,and as various changes might be made in the embodiment above set forth,it is to be understood that all matters herein set forth or shown in theaccompanying drawing are to be interpreted as illustrative and not in alimiting sense.

Having thus described my invention, 1 claim as new and desire to secureby Letters Patent:

1. In a lamp construction, a non-abrasive friction con:

trolled slide mounting comprising a cylindrical vertically disposedstandard, an electrical socket and bulb for said lamp, aclutch membercarrying said electrical socket and bulb rotatable on and axiallyslidable along said standard, said clutch member having a bore throughwhich the standard extends, one end of said bore having a reduceddiameter forming an internal shoulder, the opposite end of said borebeing internally threaded, a tubular shaped bushing of elastomericresinous plastic having non-compressible, semi-rigid, deformable,moderately self-lubricating non-abrasive properties snugly fitting saidbore, and a manually adjustable compression nut having an axial borethreaded into said clutch member bore to contact said bushing and urgingthe latter against said internal shoulder, said compression nut bore andsaid reduced diameter here being of larger diameter than the standardand the bushing being of sutficient length to minimize torque wherebysaid bushing is the sole contact between the standard and clutch member.

2. In a lamp construction, a non-abrasive friction controlled slidemounting comprising a cylindrical vertically disposed standard, anelectrical socket and bulb for said lamp, a clutch member carrying saidelectrical socket and bulb rotatable on and axially slidable along saidstandard, said clutch member having a bore through which the standardextends, one end of said bore having a reduced diameter forming a firstinternal shoulder, the opposite end of said bore being internallythreaded, a manually adjustable compression nut having an axial borethreaded into said clutch member bore terminating in an end surfaceforming a second internal shoulder spaced from said first internalshoulder, and a tubular bushing of elastomeric resinous plastic havingnon-compressible, semi-rigid, deformable, moderately self-lubricatingnonabrasive properties snugly fitting said bore between said internalshoulders, said compression nut bore and said reduced diameter borebeing of larger diameter than the standard whereby said bushing is thesole contact between the standard and clutch member, at least one ofsaid internal shoulders being beveled inwardly to deform an abutting endof said bushing against said standard on tightening of the compressionnut.

3. The lamp construction defined in claim 2 in which both of saidinternal shoulders are beveled inwardly.

References Cited by the Examiner UNITED STATES PATENTS 641,748 1/00Smith 240-81 1,557,923 10/25 Carrol 2871 14 1,854,932 4/32 Gottlieb240-81 3,048,432 8/62 Harter 287-414 X FOREIGN PATENTS 597,892 2/48Great Britain.

NORTON ANSHER, Primary Examiner.

1. IN A LAMP CONSTRUCTION, A NON-ABRASIVE FRICTION CONTROLLED SLIDEMOUNTING COMPRISING A CYLINDRICAL VERTICALLY DISPOSED STANDARD, ANELECTRICAL SOCKET AND BULB FOR SAID LAMP, A CLUTCH MEMBER CARRYING SAIDELECTRICAL SOCKET AND BULB ROTATABLE ON AND AXIALLY SLIDABLE ALONG SAIDSTANDARD, SAID CLUTCH MEMBER HAVING A BORE THROUGH WHICH THE STANDARDEXTENDS, ONE END OF SAID BORE HAVING A REDUCED DIAMETER FORMING ANINTERNAL SHOULDER, THE OPPOSITE END OF SAID BORE BEING INTERNALLYTHREADED, A TUBULAR SHAPED BUSHING OF ELASTOMERIC RESINOUS PLASTICHAVING NON-COMPRESSIBLE, SEMI-RIGID, DEFORMABLE, MODERATELYSELF-LUBRICATING NON-ABRASIVE PROPERTIES SNUGLY FITTING SAID BORE, AND AMANUALLY ADJUSTABLE COMPRESSION NUT HAVING AN